1. Field of the Invention
The present invention relates to an apparatus for measuring or controlling the separation ratio of a gas to be measured or controlled when passing through a branched passage.
2. Description of the Prior Art
The above described apparatus can be used for the measurement of the total amount of a specified gas (for example, hydrocarbon gas, NO.sub.x, SO.sub.x, etc.) in an exhaust gas of an engine and the like.
The total amount of the specified gas contained in an exhaust gas is determined on the basis of the flow rate of a small volume of an exhaust gas sampled from a branched passage, the measured concentration of the specified gas contained in the sampled exhaust gas and the separation ratio of the exhaust gas in the branched passage.
However, the conventional apparatus, which is provided with a capillary in each branched passage in order to measure or control the separation ratio of the gas, has a fatal defect in that a capillary is apt to be clogged in the case when the gas to be measured or controlled is a gas like an exhaust gas of an engine or a gas containing mist-like viscous substances.